psql:错误:无法连接到服务器:致命:用户"postgres“的对等身份验证失败

Question

我使用此处的[https://www.postgresql.org/download/linux/redhat/]命令安装并设置了postgresql-12

yum install https://download.postgresql.org/pub/repos/yum/reporpms/EL-7-x86_64/pgdg-redhat-repo-latest.noarch.rpm
yum install postgresql12
yum install postgresql12-server
/usr/pgsql-12/bin/postgresql-12-setup initdb
systemctl enable postgresql-12
systemctl start postgresql-12

然后我试着登录数据库

psql postgres postgres

我得到了错误

psql: error: could not connect to server: FATAL:  Peer authentication failed for user "postgres"

我的系统上有两个pg_hba.conf文件。我检查了身份验证设置，如下所示，这里推荐[psql: FATAL: Ident authentication failed for user "postgres"

/data/pg_data_dir/pg_hba.conf

# TYPE  DATABASE        USER            ADDRESS                 METHOD
host    all             all             0.0.0.0/0               md5

# "local" is for Unix domain socket connections only
local   all             all                                     md5
# IPv4 local connections:
host    all             all             127.0.0.1/32            trust
# IPv6 local connections:
host    all             all             ::1/128                 trust
# Allow replication connections from localhost, by a user with the
# replication privilege.
local   replication     all                                     trust
host    replication     all             127.0.0.1/32            trust
host    replication     all             ::1/128                 trust

/var/lib/pgsql/12/data/pg_hba.conf

# TYPE  DATABASE        USER            ADDRESS                 METHOD

# "local" is for Unix domain socket connections only
local   all             all                                     md5
# IPv4 local connections:
host    all             all             127.0.0.1/32            md5  
# IPv6 local connections:
host    all             all             ::1/128                 trust
# Allow replication connections from localhost, by a user with the
# replication privilege.
local   replication     all                                     trust
host    replication     all             127.0.0.1/32            trust
host    replication     all             ::1/128                 trust

身份验证设置看起来没问题，所以我不确定从这里该做什么。

Answer 1

编辑-使其更有条理，更易于使用。

首先，您需要了解每种身份验证方法的含义，在here中有大量关于这方面的信息。长话短说，在这个阶段，您可能感兴趣的是md5，它是一个哈希密码，或者trust，它不是密码。

在计算机上安装postgres后，您需要成为postgres用户，然后尝试使用psql

~# su -l postgres --assume you're postgres
~$ psql --connect

psql (xx.x ))
Type "help" for help.

postgres=#

进入后，您可以为该用户设置新密码：

postgres=# \password postgres

为了防止这种情况发生，您需要询问postgres hba文件在哪里：

postgres=# SHOW hba_file;

使用您最喜欢的文本编辑器并对其进行修改以满足您的需要。

此外，您还需要确保重新加载postgresql服务，命令为：

sudo systemctl reload postgresql-12.service